I want to control several devices using one MCU. Each device will receive either 1V or 3V depending on the application. I want to use only 2 analog pins from the MCU to send either 1V or 3V to several devices at the same time.

Is there some kind of IC or solution that assigns either inputs (1V or 3V) to the proper devices simultaneously and can change the input of the device from 1V to 3V depending on the MCU command?

Unfortunately, the DEMUX allows the selection of only 1 output and using an I/O expander is not practical because I also need this solution for other similar MCU commands. Any suggestions?

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  • \$\begingroup\$ Apart from the strange voltages, are these digital signals, as in on and off? \$\endgroup\$
    – Lundin
    Feb 13 at 11:20
  • \$\begingroup\$ the device's input is analog, and the voltages are random, just to clarify what I want. \$\endgroup\$
    – 1234
    Feb 13 at 11:24
  • 1
    \$\begingroup\$ a 74HC174 HEX D-type or octal flip flop with voltage dividers on the output? \$\endgroup\$ Feb 13 at 11:24
  • 1
    \$\begingroup\$ analog switches --> CD4051 (8 channel multiplexer), CD4052 (dual quad multiplexer), CD4053 (tripple SPDT), as wel the (A)DG series from Analog Devices, Maxim and others, they are more expensive. there is also a 16 channel multiplexer 74hc4067. \$\endgroup\$ Feb 13 at 12:46
  • \$\begingroup\$ is this a school assignment? \$\endgroup\$
    – jsotola
    Feb 13 at 15:53

1 Answer 1


The IC you are looking for is most likely an "analog switch", which is a kind of mux/demux/buffer IC with low losses and fast toggling. You enable a channel/select pin etc with a MCU logic level signal such as 3.3V and then it lets through an analog signal.

In your case you would provide a fixed 1V and a fixed 3V on the board, then use the analog switch to forward them to the various devices. As for which IC to pick it depends on the number of channels as well as MCU logic levels. Searching for "analog switches" should send you in the right direction.

  • \$\begingroup\$ It is worth considering what happens to the outputs that aren't selected. Typically an analog switch would leave them high impedance - the outputs don't remember the last voltage they were selected with. You may need a pull-up/down resistor or similar to bias them to a 'default' voltage, of a sufficiently high value so that opening the analog switch overrides the default. \$\endgroup\$ Feb 13 at 21:52

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